package string;

public class StringBUilderDemo {
    public static void main(String[] args) {
        String str = "好好学习java";
        StringBuilder builder = new StringBuilder(str);

        //append():追加内容----在末尾追加
        builder.append(",为了找个好工作");
        System.out.println(builder);

        //replace():替换部分内容(含头不含尾)
        builder.replace(9,16,"就是为了改变世界");
        System.out.println(builder);

        //delete():删除部分内容(含头不含尾)
        builder.delete(0,8);
        System.out.println(builder);

        //insert():插入内容
        builder.insert(0,"活着");
        System.out.println(builder);


        //StringBuilder的创建方式:
     /*   StringBuilder builder1 = new StringBuilder();//空字符串
        StringBuilder builder2 = new StringBuilder("abc");//abc串
        //String和StringBuilder互转:
        String str = "abc";
        StringBuilder builder3 = new StringBuilder(str);//abc串，基于String对象构造StringBuilder对象
        String str2 = builder3.toString();//将builder3转换为String
*/

    }
}
